HTMLParser.unescape in python 3.9

[TheNonexistent]

Hi. In python 3.9.0 HTMLParser.unescape was removed so the app throws error when trying to parse:

$python3 --version   
             
Python 3.9.5

and:

File ".../mdv/markdownviewer.py", line 970, in formatter
    t = html_parser.unescape(t)
AttributeError: 'HTMLParser' object has no attribute 'unescape'

[sheharyaar]

After searching a few forums, I came to know that in python 3.9.0 HTMLParser.unescape was removed

[sheharyaar]

Possible duplicate of #86 https://github.com/axiros/terminal_markdown_viewer/issues/86#issuecomment-774416153

[balazser]

the same issue is here.. :|